Zoom Team Chat allows you to send messages while outside of a meeting to contacts, groups, or entire channels. A 1-on-1 chat is a private, direct chat between you and another Zoom user. A group chat is a chat with two or more Zoom users. Chat channels can also be created and can be private or public. Private channels have invite-only membership and public channels are searchable and joinable by all members of an account.
See Zoom's article on 'Getting started with Zoom Team Chat' for the basics on Team Chat: